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Now and then, the faintest whisper returns from NASA’s distant space probes.

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Working with a local Ham wizard named Michael Staal, Comberiate fabricated eight 30-foot VHF antennas, shipped them to McMurdo Station, and mounted them atop a 65-foot-high tower. Throw in some kluged electronics and a desktop computer, and—voilà—IMP 8 data started streaming into Goddard from the South Pole. “Antarctica is a tough place to do anything like that,” Comberiate says, and after two harsh winters he disassembled the antennas and moved them to Australia.

Time is slowly catching up to IMP 8, and its data isn’t as prized as it once was. Last year’s loss of its magnetometer, whose magnetic field readings provide a context for other data sets, didn’t help. “Right now it’s like someone who is red-green colorblind,” Paularena explains. “You can still see the world, but you’re missing something.” The continuing value of IMP 8’s data will be tested later this year, when King will defend his program before a senior review board. Despite its loss of compass, there are good reasons to keep listening to what IMP 8 has to say—if for no other reason than to extend its unbroken 28-year run of solar wind data. “Sometimes I think NASA hasn’t taken sufficient pride in its long-term spacecraft,” King says.

In fact, in a world where a good VCR might last eight or 10 years, NASA’s endurance records seem nothing short of astounding. Budgets permitting, IMP 8 could continue sending its solar weather reports for years to come. The twin Voyagers could prove equally durable (the Voyager Interstellar Mission, as it’s now called, has a timeline that runs at least through 2016). No other nation’s spacefaring efforts come close to these milestones. Giotto, launched in 1985 by the European Space Agency, was tracked after plunging through two comets (Halley and Grigg-Skjellerup) until September 1992. Sakigake, another Halley watcher, remained in contact with Japanese controllers for a decade.

But the Methuselah prize may ultimately go to a spacecraft that will spend the next decade in electronic hibernation. Today NASA calls it the International Cometary Explorer, or ICE, but when launched in 1978 it was christened the International Sun-Earth Explorer 3. Under the direction of trajectory master Robert Farquhar, of the Johns Hopkins University Applied Physics Laboratory, ISEE 3 spent five years flitting here and there around the Earth-moon system. For a while it hovered near the L1 Lagrangian point, a million miles in the sun’s direction; then it crisscrossed Earth’s magnetosphere and lingered downstream for months at a time. Recast and renamed as a comet chaser, ICE dashed off to intercept the ion tail of Comet Giacobini-Zinner in September 1985.

The consummate trajectory junkie, Farquhar is never bereft of clever uses for spacecraft (see “Hang a Right at Jupiter,” Dec. 2000/Jan. 2001). He plans to revive ICE in 2010, direct it to within 125,000 miles of Earth four years later, and have it pay a return visit to Comet G-Z in 2018. He’s planned the comet encounter for September 19—a month past ICE’s 40th anniversary in space. Mark your calendars.

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